# coding: utf-8
import random
import unittest


class TestSequenceFunctions(unittest.TestCase):
    """测试random模块
    """
    def setUp(self):
        self.seq = range(10)
    def test_shuffle(self):
        # make sure the shuffled sequence does not lose any elements
        random.shuffle(self.seq)
        self.seq.sort()
        self.assertEqual(self.seq, range(10))
        # should raise an exception for an immutable sequence
        self.assertRaises(TypeError, random.shuffle, (1, 2, 3))
    def test_choice(self):
        element = random.choice(self.seq)
        self.assertTrue(element in self.seq)
    def test_sample(self):
        with self.assertRaises(ValueError):
            random.sample(self.seq, 20)
        for element in random.sample(self.seq, 5):
            self.assertTrue(element in self.seq)


if __name__ == '__main__':
    for _ in xrange(3):
        # unittest.main()
        suite = unittest.TestLoader().loadTestsFromTestCase(TestSequenceFunctions)
        unittest.TextTestRunner(verbosity=2).run(suite)